To set a display screen to portrait (vertical) orientation
1. Spin your display counter-clockwise (it matters) to orient it vertically.
2. Right-click in any empty space on your Windows “Desktop”. Select “Display Settings”.
3. Select the display (left or right side) that you would like to set as portrait.
Clicking “Identify” will cause the display number to appear on your screen, so you can confirm that you are changing the setting on the intended display.
4. Scroll down do the Display section, and change Display orientation to “Portrait
(flipped)”.
5. If all looks good, click “Keep changes”. If not, click “Revert” and ask for help.
Note that the default option is “Revert”. So, if you lose mouse control (which can happen
if you change the wrong display by mistake), press the Enter key on your keyboard to
revert back to the original setting.